ASTM D2121-16

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D2121 − 15 D2121 − 16
Standard Test Methods for
1
Polymer Content of Styrene Monomer
This standard is issued under the fixed designation D2121; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope*
1.1 These test methods cover the determination of the polymer content of styrene monomer. It should be noted, however, that
dimers and trimers are not measured by these test methods.
1.2 Test Method A, which is based on the use of a spectrophotometer or photometer, is intended for the quantitative
determination of the polymer content of styrene monomer in concentrations up to 15 mg/kg. Samples containing more than 15
mg/kg of polymer must be suitably diluted before measurement.
1.3 Test Method B is a rapid visual procedure that is intended for the approximate evaluation of polymer to a maximum
concentration of 1.0 mass %. Samples having a polymer content of 1.0 mass % or greater should be suitably diluted prior to
measurement.
1.4 In determining the conformance of the test results using this method to applicable specifications, results shall be rounded
off in accordance with the rounding-off method of Practice E29.
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use. For specific hazard statements, see Section 9.
2. Referenced Documents
2
2.1 ASTM Standards:
D2827 Specification for Styrene Monomer
D3437 Practice for Sampling and Handling Liquid Cyclic Products
D4790 Terminology of Aromatic Hydrocarbons and Related Chemicals
D6809 Guide for Quality Control and Quality Assurance Procedures for Aromatic Hydrocarbons and Related Materials
E29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
2.2 Other Document:
3
OSHA Regulations, 29CFR paragraphs 1910.1000 and 1910.1200
3. Terminology
3.1 See Terminology D4790 for definition of terms used in this test method.
TEST METHOD A—DETERMINATION OF POLYMER IN STYRENE MONOMER PHOTOMETER METHOD
4. Summary of Test Method
4.1 This test method utilizes the fact that polymers present in the monomers are insoluble in methanol. The polymer content
of styrene monomer is determined by measurement of the degree of turbidity produced by the addition of dry methanol to the
styrene sample.
1
These test methods are under the jurisdiction of ASTM Committee D16 on Aromatic Hydrocarbons and Related Chemicals and are the direct responsibility of
Subcommittee D16.07 on Styrene, Ethylbenzene and C9 and C10 Aromatic Hydrocarbons.
Current edition approved March 15, 2015June 1, 2016. Published March 2015July 2016. Originally approved in 1962. Last previous edition approved in 20072015 as
D2121 – 07.D2121 – 15. DOI: 10.1520/D2121-15.10.1520/D2121-16.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
3
Available from U.S. Government Printing Office Superintendent of Documents, 732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http://
www.access.gpo.gov.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
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D2121 − 16
5. Significance and Use
5.1 This test method can be used for determining polymer concentrations in styrene monomer.
5.2 This test method will not detect dimers and trimers.
5.3 This test method can be used for plant control and for specification analysis.
6. Interferences
6.1 Small changes in turbidity may occur with time. It is, therefore, important that the absorbance of calibration mixtures and
samples be determined after standing the same length of time.
6.2 Hexane is used for two reasons:
6.2.1 To block out a
...

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D2121 − 16
Standard Test Methods for
1
Polymer Content of Styrene Monomer
This standard is issued under the fixed designation D2121; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope* D3437 Practice for Sampling and Handling Liquid Cyclic
Products
1.1 These test methods cover the determination of the
D4790 Terminology of Aromatic Hydrocarbons and Related
polymer content of styrene monomer. It should be noted,
Chemicals
however, that dimers and trimers are not measured by these test
D6809 Guide for Quality Control and Quality Assurance
methods.
Procedures for Aromatic Hydrocarbons and Related Ma-
1.2 Test Method A, which is based on the use of a spectro-
terials
photometer or photometer, is intended for the quantitative
E29 Practice for Using Significant Digits in Test Data to
determination of the polymer content of styrene monomer in
Determine Conformance with Specifications
concentrations up to 15 mg/kg. Samples containing more than
E691 Practice for Conducting an Interlaboratory Study to
15 mg/kg of polymer must be suitably diluted before measure-
Determine the Precision of a Test Method
ment.
2.2 Other Document:
1.3 Test Method B is a rapid visual procedure that is
OSHA Regulations, 29CFR paragraphs 1910.1000 and
3
intended for the approximate evaluation of polymer to a
1910.1200
maximum concentration of 1.0 mass %. Samples having a
3. Terminology
polymer content of 1.0 mass % or greater should be suitably
3.1 See Terminology D4790 for definition of terms used in
diluted prior to measurement.
this test method.
1.4 In determining the conformance of the test results using
this method to applicable specifications, results shall be
TEST METHOD A—DETERMINATION OF POLYMER
rounded off in accordance with the rounding-off method of
IN STYRENE MONOMER PHOTOMETER METHOD
Practice E29.
4. Summary of Test Method
1.5 The values stated in SI units are to be regarded as
standard. No other units of measurement are included in this 4.1 This test method utilizes the fact that polymers present
in the monomers are insoluble in methanol. The polymer
standard.
content of styrene monomer is determined by measurement of
1.6 This standard does not purport to address all of the
the degree of turbidity produced by the addition of dry
safety concerns, if any, associated with its use. It is the
methanol to the styrene sample.
responsibility of the user of this standard to establish appro-
priate safety and health practices and determine the applica-
5. Significance and Use
bility of regulatory limitations prior to use. For specific hazard
5.1 This test method can be used for determining polymer
statements, see Section 9.
concentrations in styrene monomer.
2. Referenced Documents
5.2 This test method will not detect dimers and trimers.
2
2.1 ASTM Standards:
5.3 This test method can be used for plant control and for
D2827 Specification for Styrene Monomer
specification analysis.
1
6. Interferences
These test methods are under the jurisdiction of ASTM Committee D16 on
Aromatic Hydrocarbons and Related Chemicals and are the direct responsibility of
6.1 Small changes in turbidity may occur with time. It is,
Subcommittee D16.07 on Styrene, Ethylbenzene and C9 and C10 Aromatic
therefore, important that the absorbance of calibration mixtures
Hydrocarbons.
Current edition approved June 1, 2016. Published July 2016. Originally approved
and samples be determined after standing the same length of
in 1962. Last previous edition approved in 2015 as D2121 – 15. DOI: 10.1520/
time.
D2121-16.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
3
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Available from U.S. Government Printing Office Superintendent of Documents,
Standards volume information, refer to the standard’s Document Summary page on 732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http://
the ASTM website. www.access.gpo.gov.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D2121 − 16
6.2 Hexane is used for two reasons: 9.3 Consult current OSHA regulations, local regulations,
6.2.1 To block out any color in the styrene, and and suppliers’ Safety Data Sheets for all materials used in these
6.2.2 To indicate dissolved water in the styrene. test methods.
7. Apparatus
10. Sampling and Handling
7.1 Pipets, 10 and 15-mL.
10.1 Sample the material in accordance with P
...